As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is the information handling system. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more information handling systems, data storage systems, and networking systems.
Personal computer (“PC”) systems in general and IBM compatible personal computers in particular are types of information handling systems that have attained widespread use. These information handling systems handle information and primarily give independent computing power to a single user (or a relatively small group of users in the case of a PC network). Such information handling systems are typically inexpensively priced and provide computing power to many segments of today's modern society.
An information handling system can usually be defined as a desktop, floor-standing, or portable microcomputer that includes a system unit having a central processing unit (“CPU” or a “processor”), volatile and/or non-volatile memory, a display monitor, a keyboard, one or more floppy diskette drives, a hard disc storage device, an optional DVD or CD-ROM drive, and an optional printer. An information handling system typically also includes a commercially available operating system, such as Microsoft Windows NT or Linux. An information handling system may also include one or more input/output (“I/O”) devices coupled to the system processor to perform specialized functions. Examples of I/O devices include, but are not limited to, keyboard interfaces with keyboard controllers, floppy diskette drive controllers, modems, sound and video devices, and specialized communication devices.
Personal computers typically include peripheral storage devices such as disc drives using removable storage media. The removable storage media is typically used to store and/or load software, data, and documentation. Examples of disc drives with removable storage media include CD-ROM, CD-RW, DVD-ROM, floppy, Zip disc and removable hard disc drives.
The personal computer (PC) aspect of the information handling system business is rapidly moving toward “build-to-order” manufacturing. In such an environment, the customer typically enters a purchase order for a PC by selecting specific options such as CPU model/speed, memory size, hard disc drive size, peripheral devices such as display monitor size, resolution, keyboard, CD-RW, DVD, printers as well as others. The PC purchase order usually includes a choice for an operating system such as Windows ME™, Windows 2000™ or in some cases Linux. In the build-to-order manufacturing environment, the PC manufacturer assembles the PC hardware in compliance with the purchase order.
After completion of the hardware and software assembly process, an information handling system typically undergoes extensive inspection and testing. The PC manufacturer typically ships the custom manufactured PC to the customer within a few days after receipt of a purchase order. Typically, a PC manufacturer may ship several thousand “build-to-order” PCs or information handling systems every day.
During the manufacturing process of a personal computer, the inspection and testing phase is typically important to identify product defects. Generally, it is more cost effective to identify and fix product defects before shipment to a customer site. Testing personal computer peripheral devices such as disc drives with removable storage media can be time-consuming. For example, the testing phase of the CD-ROM device typically involves manually inserting a test CD-ROM in the drive and conducting the test procedure. The “build-to-order” manufacturing process of a personal computer as well as the manufacturing line for removable storage media drive devices themselves typically involve an assembly line operation capable of producing thousands of units each hour. The step of manually inserting removable media for test purposes typically slows down the manufacturing process, is a potential source of false failures, and adds to product costs.
FIG. 1A is a schematic diagram generally illustrating the structure of one type of removable storage media drive device, CD-ROM drive 100. As illustrated in FIG. 1A, a spindle motor 102 is preferably included in CD-ROM drive 100 to rotate CD-ROM disc 104 (CD-ROM) when properly seated on turntable 106. For purposes of the present disclosure, CD-ROM 104 may be used to refer to a CD-ROM, a DVD-ROM, a CD-RW, other optical media as well as magnetic and other forms of storage media.
Generally upon inserting CD-ROM disc 104 in CD-ROM drive 100, a clamp assembly 108 may be used to secure the position of CD-ROM disc 104 on turntable 106 such that CD-ROM disc 104 may be frictionally coupled to turntable 106. Several types of clamp mechanisms 108 are available and the type chosen typically depends on the dimensions of CD-ROM drive 100. A disc controller 112 operable to control overall CD-ROM disc drive system 100, including spindle motor 102 and sensor device 110, is also preferably included. Disc controller 112 typically includes a microprocessor (not expressly shown) or a digital signal processor (not expressly shown) configured to control the operation of CD-ROM disc drive 110.
For CD-ROM and DVD-ROM read only devices, one or more low-power laser diodes, a lens, a focusing coil, other optical elements and a light detecting device (not expressly shown) are typically included in sensor device assembly 110, for example. For CD-RW and other recordable optical devices, sensor device assembly 110 is similar with a laser diode capable of pulsing to higher power for writing information to a disc, for example.
Conventionally, information is encoded in a spiral track (not expressly shown) contained on one side of CD-ROM disc 104. The spiral track is typically read optically by sensor device 110, which includes a non-contact head, and which scans approximately radially as the CD-ROM disc 104 spins above it.
FIG. 1B is a schematic diagram illustrating land 118 and pit 116 formations included in a typical spiral track of CD-ROM disc 104. In one embodiment, CD-ROM disc 104 preferably includes a disc substrate 114 in which pits 116 and lands 118 may be formed to store information. Generally to enable information or data to be read by a laser of sensor device 110, a reflective layer 120 is preferably deposited on disc substrate 114. Typically disposed on reflective layer 120 is protective layer 122. Finally, many CD-ROM discs 104 may be finished with a disc label 124 disposed on protective layer 122.
In general, a CD-ROM spiral track contains shallow depressions, a depression being referred to as a pit 116, in a reflective layer 118. The length of these pits and the length of the areas between them, often called land 118, may be combined to encode binary information. During a read operation, a low power laser from sensor device 110, also referred to as an optical head in the case of a CD-ROM disc drive 100, is focused on the spiral track and may be reflected back into a light detection diode of sensor device 110. Due to the optical characteristics of the disc and the wavelength of light used, the quantity of reflected light varies depending on whether the beam is on land 118 or pit 116. The modulated, reflected light may then be converted to a radio frequency, raw data signal by the light detector diode (not expressly shown) of sensor device 110. Other optical devices, such as a CD-RW recordable device, DVD-ROM read devices and recordable DVD devices, operate in essentially the same manner except where pits 116 may be replaced by a spiral groove (not expressly shown) which may contain written marks.